Differential requirements of APEX1 or TRIP6/CCT7 for TFEB activation under several cellular stressors. (A) Representative immunoblots of LC3 and GAPDH in WT, ATG7 KO, or FIP200 KO HeLa cells were either untreated (control) or treated with MK6-83 for 3 h. Values indicating the amount of LC3-II were normalized to the levels of the GAPDH in each. (B–D) Representative fluorescence images of WT or ATG7 KO HeLa cells transiently expressing mNG::TRIP6 or mNG::CCT7, either untreated (control) or treated with O/A or etoposide or MK6-83. (E) Representative fluorescence images of WT HeLa cells stably expressing TFEB::mNG, either untreated (control) or treated with O/A for 3 h. Cells were transfected with siLuc or siAPEX1. (F) Quantification of image data shown in E (n = 3 biologically independent samples). (G) Representative fluorescence images of WT HeLa cells stably expressing TFEB::mNG, either untreated (control) or treated with etoposide for 24 h. Cells were transfected with siLuc or siAPEX1. (H) Quantification of image data shown in G (n = 3 biologically independent samples). (I) Representative fluorescence images of WT HeLa cells stably expressing TFEB::mNG, either untreated (control) or treated with MK6-83 for 3 h. Cells were transfected with siLuc or siAPEX1. (J) Quantification of image data shown in I (n = 3 biologically independent samples). (B–D, E, G, and I) Scale bars, 50 µm. (E, G, and I) Arrowheads indicate nuclear-localized TFEB::mNG. (F, H, and J) Relative value of the TFEB nuclear translocation rate under drug treatment conditions compared with that under basal (control) conditions. A t test was used to compare the mean values of TFEB nuclear translocation rate in each condition. Source data are available for this figure: SourceData FS7.